JP2635875B2 - Sheet post-processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus which is used in an image forming apparatus such as a copying machine or a laser beam printer and performs post-processing such as binding or punching on copied sheets.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus such as a copying machine for copying an image of a document on a sheet is provided with a sheet post-processing apparatus for binding a plurality of sheets. Such a sheet post-processing apparatus includes a staple mode in which a sheet conveyed from the body main body is subjected to post-binding processing, and then the bound sheet is discharged out of the apparatus. One after another without post-processing the incoming sheets
There are two modes, an offset mode in which sheets are ejected out of the apparatus one by one. And in the above staple mode,
For example, as shown in FIG. 26A, a copied sheet S conveyed from the machine body side through the post-processing conveyance path 71 is aligned and stacked on the staple plate 72, and then incorporated. The stapler 73 performs bookbinding by binding with staples. The bound sheet S (hereinafter, referred to as a bookbinding sheet) is rotated by the discharge roller 74 and pushed out by the pushing member 7.
The sheet is discharged onto the discharge tray 76 by the advance movement of No. 5.

On the other hand, in the offset mode, FIG.
As shown in (b), the driven roller 77 disposed above the discharge roller 74 is rotated to obtain a contact state between the driven roller 77 and the discharge roller 74, so that the post-processing conveyance path from the machine body side. The copied sheet S conveyed through 71 is
The sheet is sandwiched between the rollers 74 and 77 and discharged directly onto the discharge tray 76.

In the staple mode as described above, a discharge tray 76 for stacking bookbinding sheets S is provided as shown in FIG.
As shown in FIG. 28, the cutout portion 76a is formed at one corner on the side of attachment to the apparatus, and as shown in FIG. 28, the binding portion St of the bookbinding sheet S is dropped into the cutout portion 76a by its own weight and is released. The alignment of the bookbinding sheet S on the sheet 76 is improved.

[0005]

However, as described above, the binding portion St of the bookbinding sheet S is notched 7 by its own weight.
6a, and the bound sheet S on the discharge tray 76
In the configuration for improving the consistency of the sheets, the amount of the book sheet S stacked on the discharge tray 76 and the amount of paper falling into the cutout portion 76a differ depending on the paper quality. For this reason, when there is a limit in the drop of the binding unit St due to its own weight, such as when the amount of the bound binding sheets S is large or when the paper quality of the binding sheets S is hard, the binding sheet S jumps up at the binding unit St. This leads to a decrease in consistency. Further, the amount of drop of the binding portion St into the notch portion 76a due to its own weight is as follows:
By increasing the area of the cutout portion 76a formed in the discharge tray 76, the binding portion St can be surely formed in view of the limit of the area of the cutout portion 76a that can be formed in the discharge tray 76, although this is slightly improved. There is a problem that it cannot be dropped into the notch 76a.

[0006]

According to a first aspect of the present invention, there is provided a sheet post-processing apparatus for binding a sheet loaded from an image forming apparatus and stacked on a post-processing plate. In the sheet post-processing apparatus that performs binding by bookbinding, and then discharges the bound sheets to a discharge tray by a discharge unit provided at one end of the post-processing plate on the discharge side, the following means are taken. .

That is, the discharge tray is attached to the apparatus at a position below the discharge means, and a cutout for releasing a binding portion of a bound sheet is formed on a surface facing the discharge means. Further, since at least one of the discharge tray and the discharge means is provided so as to be able to move up and down in the vertical direction, the sheet on the discharge tray is sandwiched between the discharge tray and the discharge means.

According to a second aspect of the present invention, there is provided a sheet post-processing apparatus for performing a predetermined post-processing on a sheet carried in from an image forming apparatus and stacked on a post-processing plate. , by the discharge means provided sheets this post-processing is applied to one end of the discharge side of the post-processing board, the discharge
In a sheet post-processing apparatus for discharging a sheet to a discharge tray attached to an image forming apparatus at a position below the means, the following means is employed.

In other words, the discharge tray is connected to the image forming apparatus.
Extends diagonally upward from the mounting position
A concave relief portion for the discharging means is formed on the upper surface of the discharge tray on the
The bearing surface for receiving the sheet is located above the relief
The support surface is formed so as to be able to move up and down in the vertical direction, so that the support surface can be arranged on the same surface as the upper surface of the post-processing plate ,
With the provision of the tray angle adjusting means for moving the support surface forward and backward, the tray angle between the support surface and the relief portion is made variable in accordance with the amount of sheets stacked on the discharge tray .

[0010]

According to the first aspect of the present invention, the sheets bound by the bookbinding unit and then stacked on the discharge tray are sandwiched between the discharge tray and the discharge unit, thereby binding the sheets. Part is pushed into a notch formed in the discharge tray. For this reason, it is possible to reliably prevent the binding portion of the sheet from jumping up on the discharge tray, and as a result, it is possible to improve the consistency of the bound sheets on the discharge tray.

According to the second aspect of the present invention, since the discharge tray is provided with the tray angle adjusting means, the tray angle between the bearing surface of the discharge tray and the relief portion is stacked on the discharge tray. It can be made variable depending on the amount of sheets. For this reason, when the amount of sheets stacked on the discharge tray is small, the tray angle is set so as to optimally support the sheets discharged from the post-processing plate,
When the amount of sheets stacked on the discharge tray is large, the bearing angle and the relief portion are arranged substantially in a straight line by setting the tray angle to approximately 180 degrees, and the step between the bearing surface and the relief portion is formed. Swelling of the sheet due to the above can be avoided.

[0012]

1 to 25 show an embodiment of the present invention.
This will be described below. In this embodiment, a case where the sheet post-processing apparatus is applied to a copying machine as an image forming apparatus is illustrated.

As shown in FIG. 1, the copying machine according to the present embodiment has a body main body 1 for copying an image of a document M onto a sheet S. A document transporting device 30 for transporting the document M to the exposure section 2 formed on the upper end surface of the document is provided.

The main body 1 is provided with an exposure glass 3 forming an exposure section 2 at an upper end thereof.
An optical system 9 including a light source lamp 4, mirrors 5, 6, 7 and a lens 8, and a photosensitive drum 10 are disposed below the light source lamp 4. The optical system 9 optically scans the original M conveyed to the exposure unit 2 by the original conveying device 30 to be described later with the light emitted from the light source lamp 4, and reflects the reflected light to each of the mirrors 5 and 6. By irradiating the exposure point A on the surface of the photoconductor drum 10 via the lens 7 and the lens 8, the surface of the photoconductor drum 10 uniformly charged by the main charger unit 11, which will be described later, is statically corresponding to the image of the original M An electrostatic latent image is formed.

Around the photosensitive drum 10, a main charger unit 11 for charging the surface of the photosensitive drum 10 to a predetermined potential as described above, and a developing unit 12
, A transfer charger 13 and a peeling charger 14 are provided, and the electrostatic latent image formed on the surface of the photosensitive drum 10 is developed as a toner image by the developing unit 12, and then this toner image is transferred. The image is transferred to a sheet S conveyed by a charger 13 through a sheet conveying path 15 described later. The release charger 14 separates the sheet S on which the toner image is transferred from the photosensitive drum 10.

A sheet conveying path 15 for conveying a sheet S for transferring a toner image is provided below the photosensitive drum 10. On the upstream side of the sheet conveying path 15, a sheet feeding table 19 having sheet feeding rollers 16, 17, and 18, a sheet feeding cassette 20, and a sheet feeding deck 21 are provided, respectively. Sheets S placed or accommodated on the table 19, the sheet cassette 20, and the sheet deck 21
Is supplied to the photosensitive drum 10 through the sheet conveying path 15. On the other hand, a transport belt 22 that transports the sheet S to which the toner image has been transferred and a fixing device 23 that fixes the toner image onto the sheet S are disposed downstream of the sheet transport path 15.

Downstream of the fixing device 23, the sheet S is transported in a direction opposite to the sheet
5 is provided. The re-conveying path 25 forms a circulation path for conveying the sheet S on which the toner image has been transferred by the photosensitive drum 10 to the photosensitive drum 10 again. It enables double-sided copying.

The document transport device 30 has a document transport path 31 for transporting the document M to the exposure unit 2 formed on the upper end surface of the body 1 of the machine. The document conveying path 31 forms a circulation path. In the path, a document tray 32 for stacking the documents M and a document M stacked on the document tray 32 are sequentially supplied to the exposure unit 2. A feeding belt 33 for feeding,
A transport belt 34 is provided in contact with the exposure glass 3 forming the exposure unit 2 and forms a transport path for the original M with the exposure glass 3. Then, the original transport device 3
Reference numeral 0 indicates that the document M on the document tray 32 is fed to the exposure unit 2 by the feeding belt 33 and the document M is positioned at a predetermined position on the exposure glass 3 by the transport belt 34. 4, the original M is arranged in the state of the optical scanning.

Further, in the copying machine according to the present embodiment, a sheet post-processing device 40 is disposed downstream of the above-mentioned sheet conveying path 15.

As shown in FIG. 2, the sheet post-processing apparatus 40 includes a post-processing conveyance path 41 for conveying the sheet S conveyed from the body 1 in the apparatus 40 and a staple staple for aligning the sheet S. Binding means 45 for performing bookbinding processing according to
And a discharge unit 51 for discharging the bound sheets S from the inside of the apparatus 40, and a discharge tray 56 for placing the sheets S discharged from the inside of the apparatus 40.

The post-processing conveyance path 41 is formed at one end thereof with a carry-in port 41a for carrying the sheet S conveyed from the machine body 1, and is bifurcated in the middle of the path to form a two-stage upper and lower section. Bypass 41b and main path 41c
Are formed. In addition, the post-processing transport path 41 includes:
At each end of the bypass 41b and the main path 41c,
A pair of upper and lower conveying rollers 42 and 43 are provided, and a deflector 44 rotatable in the B ₁ -B ₂ direction is provided at a branch point between the bypass 41b and the main path 41c. Is switched to either the bypass 41b or the main path 41c. Further, as shown in FIG. 3, the post-processing conveyance path 41 includes a bypass 41b and a main path 41.
c and the sheet detection switch SW ₁ · SW ₂ for detecting the sheet S is disposed respectively on each path of the detection operation of each sheet S by these sheet detection switch SW ₁ · SW _2, as described below The drive control of the transport roller 43 is performed.

The bookbinding means 45 includes a staple plate 46 as a post-processing plate, a width shift plate 47, and a paddle 4
8 and a stapler 49.

The staple plate 46 has one end thereof disposed at a discharge port 40a formed on the outer surface of the apparatus 40, and the other end thereof is inclined downward with respect to the one end. The sheet S to be bound (stapled) is disposed below the path 41 and is stacked. The staple plate 46 is provided with a sheet detection switch (not shown) so that the presence or absence of the sheet S on the staple plate 46 is detected.

The width shift plate 47 includes a staple plate 46.
And a staple plate 46 which is provided so as to be able to advance and retreat in a direction perpendicular to the paper surface of FIG.
The upper sheet S is aligned in the width direction. The paddle 48 has a wing portion whose staple plate 46
The sheet S on the staple plate 46 is aligned in the transport direction while being provided so as to be in contact with the upper surface of the lower end of the staple plate 46 and rotatable in the C direction. The stapler 49 is disposed at a side position of the staple plate 46 to which the paddle 48 is in contact, and is configured to bind the sheets S stacked on the staple plate 46 with staples and bind the book. A stopper 50 is provided on the lower end side of the staple plate 46, and the stopper 50 is used to position the rear end of the sheets S stacked on the staple plate 46, so that the paddle 48 The alignment of the sheet S in the transport direction is assisted.

The discharging means 51 comprises a pushing member 52, a discharging roller 53, and a driven roller 54.

The extruding member 52 is disposed on an extension of the lower end of the staple plate 46, and is provided so as to be able to advance and retreat in the direction D ₁ -D ₂ along the upper surface of the staple plate 46, thereby forming a bound sheet. S is pushed out from the staple plate 46 toward the discharge port 40a. The discharge roller 53 is rotatably supported by the upper end portion of the staple plate 46 so as to be rotatable in the G ₁ -G ₂ directions. On the other hand, the driven roller 54
Has its rotating shaft is pivotally supported at one end of the arm member 55, the other end of the arm member 55 is rotatably provided on the F ₁ -F ₂ direction about the fulcrum E . Then, discharge rollers 53 described above, the staple mode to be described later, the staple plate 4 by the rotation of the G ₂ direction
While assist alignment of the conveying direction of the sheet S to be stacked on the 6, so as to discharge the sheet S bound by the rotation of the G ₁ direction to the discharge tray 56. The driven roller 54 is offset mode to be described later, in accordance with the rotation of the G ₁ direction of the discharge roller 53, the arm member 5
5 by being rotated in the F ₂ direction, and sandwiched the sheets S between the discharge roller 53, which is directly sheet S from the post-processing transport path 41 to discharge onto the discharge tray 56.
The rollers 53 and 54 are, as shown in FIG.
At contact state between each other in the offset mode, so as to constitute a sheet detection switch SW ₃ for detecting the sheet S.

The discharge tray 56 is attached to the apparatus 40 at a position below the discharge roller 53, and the elevator unit 57 and the shift unit 5
By 8 and is arranged, and H ₁ -H ₂ direction which is the vertical direction, is provided to be retractable in the direction perpendicular to the plane of FIG. 2, the tray position is adjusted according to the bearing for the sheet S It has become so. Incidentally, the advancing movement of the H ₁ direction of the discharge tray 56, being adapted to the upper limit detection is performed by an actuator 59 disposed in the discharge roller 53 as shown in FIG. 5, also, the actuator 59 ,
As shown in FIG. 6 (a) (b), by causing the H ₁ rotates in the J direction engaging portion 59a around the fulcrum I along with the advancing movement in the direction of the discharge tray 56 engaged with the sensor 60 ,
The discharge tray 56 is stopped at a position where the sheet S is sandwiched between the discharge tray 53 and the discharge roller 53.

The discharge tray 56 has a concave portion on the side of attachment to the apparatus 40 and is formed as a relief portion 56a for the discharge roller 53. One corner of a surface of the relief portion 56a opposed to the discharge roller 53 has: A cutout portion 56b as shown in FIG. 7 is formed to allow a binding portion St of the bookbinding sheet S described later to escape. On the other hand, the discharge tray 56
The supporting surface 56c of the sheet S in the above is parallel to the upper surface of the staple plate 46. further,
As shown in FIG. 8, the discharge tray 56 has a bearing surface 56.
c is pivotally mounted on the tip of the escape portion 56a so as to be rotatable about a fulcrum K, and the tip side of the escape portion 56a is at a bending point L.
, And is pivotally mounted about the fulcrum K.
Is attached to the discharge tray 56, the tray angle α between the bearing surface 56c and the relief portion 56a is adjusted by attaching a spring 61 as tray angle adjusting means.
Are variably provided in accordance with the amount of.

In the above configuration, the process of transporting the sheet S in the sheet post-processing apparatus 40 will be described below. In the following description, the offset mode in which the sheets S conveyed from the main body 1 are discharged to the discharge tray 56 one by one without performing post-processing on the sheets S conveyed from the main body 1, After the post-binding process, the staple (single) mode in which only one copy of a sheet S (hereinafter, referred to as a bookbinding sheet S) is discharged to a discharge tray 56, and the sheet S conveyed from the machine body 1 After a post-binding process is performed, a description will be given of the staple (multi) mode in which a plurality of sets of bound sheets S are sequentially discharged to the discharge tray 56.

First, in the offset mode, as shown in the flowchart of FIG. 9, when the sheet post-processing apparatus 40 receives the number of offset sheets from the machine body 1 (S1), the number of offset sheets is set in the apparatus 40 (S2). ). Next, when the device 40 receives an operation start from the body 1 (S3), a start process is performed (S4), and the number of processed sheets is cleared (S5).

Thereafter, the sheet S on which the image of the document M has been copied by the body 1 is carried into the apparatus 40 through the carry-in port 41a, and after passing through the main path 41c, the rollers 5
The sheet is sandwiched between 3.54 and discharged to a discharge tray 56.
At this time, the sheet S is set to the sheet detection switch SW.
The _second ON state transport in the main path 41c is detected (S6), also, the ON state (S7) of the sheet detection switch SW _3, and the transport and passage of between the rollers 53, 54 by the OFF state (S8) Is detected, and the number of processed sheets is increased (S9).

Next, it is determined whether or not the number of processed sheets increased as described above matches the number of offset sheets (S1).
0). If the number of processed sheets does not match the number of offset sheets in S10, the process returns to S6 again. On the other hand, if the processed number matches the offset number, the processed number is cleared (S
11) Then, the lowering (S12), the offset (S13) and the raising (S14) of the discharge tray 56 are sequentially performed.

Then, the presence or absence of the end reception from the body main body 1 to the apparatus 40 is determined (S15). If there is no end reception, the process returns to S6 again. If there is the end reception, the end processing is performed. (S16) The offset mode as described above is terminated.

Next, in the staple (single) mode, as shown in the flowchart of FIG. 10, when the sheet post-processing apparatus 40 receives the number of staples from the machine body 1 (S21), the number of staples is set in the apparatus 40. Is performed (S22). Next, when the apparatus 40 receives an operation start from the body 1 (S23), a start process is performed (S24), and the number of processed sheets is cleared (S25).

Thereafter, the sheet S on which the image of the document M has been copied by the body 1 is carried into the apparatus 40 through the carry-in port 41a, passes through the main path 41c, and is discharged onto the staple plate 46. Paper. At this time, the sheet S described above, the sheet detection switch SW ₂ in the ON state (S2
6) and the OFF state (S27), the main path 41
The conveyance at c is detected, whereby the timer of the device 40 is cleared (S28), and the number of processed sheets is increased (S29). When the predetermined time set by the timer elapses (S30), it is determined that the discharge of the sheet S onto the stapling plate 46 is completed.
The sheet S on the stapling plate 46 is aligned in the width direction by the width shift plate 47 (S31).

Next, it is determined whether or not the number of processed sheets increased as described above matches the number of staples (S3).
2). If the number of processed sheets does not match the number of offset sheets in S32, the process returns to S26. On the other hand, if the number of processed sheets coincides with the number of staples, the number of processed sheets is cleared (S33), and then the sheet S on the staple plate 46 is rotated by the paddle 48 in the direction C and the discharge roller 53 is rotated by G. _The paper is aligned in the transport direction by rotation in _two directions, and is stapled by the staples of the stapler 49 (S34).

[0037] Then, the bookbinding sheet S which stapling processing has been performed as described above is extruded advancing movement in the D ₁ direction member 52, and the staple plate upper 46 by the rotation of the G ₁ direction of the discharge roller 53 From the output tray 56
(S35). Then, after the discharge tray 56 is adjusted (S36), when the apparatus 40 receives an operation end from the machine body 1 (S37), an end process is performed (S38), and the above-described staple (single) is performed. The mode is terminated.

Next, in the staple (multi) mode, as shown in the flow charts of FIGS. 11 to 15, when the sheet post-processing apparatus 40 receives the number of staples from the machine body 1 (S41), the staples are stored in the apparatus 40. The number is set (S42).

Next, when the apparatus 40 receives an operation start from the body 1 (S43), a start process is performed (S44), and the number of processed sheets is cleared (S45).

Thereafter, the sheet S on which the image of the document M has been copied by the body 1 is carried into the apparatus 40 through the carry-in port 41a, passes through the main path 41c, and is discharged onto the staple plate 46. Paper. At this time, the sheet S described above is conveyed in the main path 41c by the ON state of the sheet detection switch SW ₂ is detected (S46), then whether or not the sheet detection switch SW ₂ is turned OFF is determined (S47 ). At S47, if the sheet detection switch SW ₂ is still ON state, the process proceeds to S48, the bookbinding sheet S is whether already discharged from above the staple plate 46 is determined. If the bookbinding sheet S has not yet been discharged from the staple plate 46 in S48, the bookbinding sheet S is discharged to the discharge tray 56 by the pushing member 52 and the discharge roller 53 (S49), and the process returns to S47 again. On the other hand, if the bookbinding sheet S has been discharged from the staple plate 46, the process proceeds to S50, where it is determined whether or not the discharge tray 56 has been adjusted. In S50, if the discharge tray 56 has been adjusted, the process directly returns to S47. If the discharge tray 56 has not been adjusted, the discharge tray 56 is adjusted (S51), and the process returns to S47. Then, in S47, when the OFF state of the sheet detection switch SW ₂ is detected, along with this, the timer device 40 is cleared (S52), also the number of processing sheets is up (S53).

Next, it is determined whether or not the number of processed sheets increased as described above is the first one (S54). S54
If the number of processed sheets is not the first sheet, the process proceeds to S66 described later.
On the other hand, if the number of sheets to be processed is the first sheet, the process proceeds to S55, and it is determined whether or not the preparation of the stapling plate 46 is OK. In S55, the staple plate 4
If the staple plate 46 has not been prepared, the process proceeds to S66. If the staple plate 46 has not been prepared, the rotation of the transport roller 43 is stopped to stop the transport of the first sheet S. (S56), and the deflector 4
4 is rotated in the B ₁ direction, the conveying path of the sheet S is switched to the bypass 41b (S57).

Next, whether or not the second sheet S is being conveyed to the bypass 41b is determined by the sheet detection switch SW.
It is determined by detecting the ON state of ₁ (S58).
At S58, if it is not the sheet detection switch SW ₁ is still ON, the process proceeds to S59, whether bookbinding sheet S is already discharged is determined. If the bookbinding sheet S has not yet been discharged from the staple plate 46 in S59, the bookbinding sheet S is discharged to the discharge tray 56 by the pushing member 52 and the discharge roller 53 (S6).
0), while returning to S58 again, the staple plate 4
6. If the bookbinding sheet S has been discharged from above, the process proceeds to S61.
Then, it is determined whether or not the discharge tray 56 has been adjusted.
If the discharge tray 56 has been adjusted in S61,
On the other hand, if the ejection tray 56 has not been adjusted, the ejection tray 56 is adjusted (S62), and the process returns to S58. Then, in S58, the ON state of the seat detection switch SW ₁ is detected, then the sheet detection switch S
By the OFF state of the W ₁ is detected (S63), the deflector 44 is rotated in the B ₂ direction, the conveying path of the sheet S is switched to the main path 41c (S64), also the transport roller 43 is rotated Then, the conveyance of the first sheet S is restarted (S65). As a result, the first sheet S passing through the main path 41c and the second sheet S passing through the bypass 41b are discharged synchronously on the staple plate 46.

Next, the flow returns to S52 again, the timer of the apparatus 40 is cleared, and the number of processed sheets is increased (S52).
53), and proceed to S54. If it is determined in S54 that the number of processed sheets is not the first sheet, then the process proceeds to S66, in which it is determined whether or not a predetermined time set by the timer has elapsed. When the predetermined time has elapsed, it is determined that the discharge of the sheet S onto the staple plate 46 is completed, and the sheet S on the staple plate 46 is aligned in the width direction by the width diverter 47 (S67). Then, it is determined whether or not the number of processed sheets S matches the number of staples (S68). If the number of processed sheets does not match the number of staples in S68, the process returns to S46. on the other hand,
If the number of processed sheets matches the number of staples, the number of processed sheets is cleared (S69), and then the sheet S on the staple plate 46 is rotated by the paddle 48 in the C direction.
And while being aligned in the conveying direction by the rotation of the G ₂ direction of the discharge roller 53, the staple processing stapled by staple of the stapler 49 is subjected (S70),
After that, the process returns to S46 again.

[0044] Then, at S46, when the detection of the sheet S by the sheet detection switch SW ₂ is eliminated, the process proceeds to S71, whether bookbinding sheet S is already discharged is determined.
If the bookbinding sheet S has not yet been discharged from the staple plate 46 at S71, the bookbinding sheet S is discharged by the pushing member 52 and the discharge roller 53 to the discharge tray 56.
(S72), and returns to S46 again. On the other hand, if the bookbinding sheet S has been discharged from the staple plate 46, the process proceeds to S73, where it is determined whether or not the discharge tray 56 has been adjusted. If the ejection tray 56 has not been adjusted in S73, the ejection tray 56 is adjusted (S7).
4) While returning to S46, if the discharge tray 56 has been adjusted, the process proceeds to S75, where it is determined whether or not the apparatus 40 has received an operation end from the machine body 1. In S75, if the operation end has not been received, the process returns to S46. On the other hand, if the operation end has been received, an end process is performed (S7).
6) The staple (multi) mode as described above is terminated.

As described above, the present sheet post-processing apparatus 40
As shown in FIG. 16A, when performing bookbinding of a plurality of copies, as shown in FIG. 16A, while performing a predetermined bookbinding process on the first sheet S on the stapling plate 46, the sheet is conveyed from the body 1 side. to come the sheet S ₁ of the following first sheet main path 41
transported by c, then, by stopping the rotation of the transport roller 43 temporarily stops the conveyance of the sheet S _1. Next, FIG.
As shown in 6 (b), by switching the deflector 44 conveys the second sheet S ₂ in the bypass 41b,
After earning the bookbinding time for the first sheet S,
By restarting the rotation of the transport roller 43, the transport of the _first sheet S1 is resumed, and as shown in FIG.
The first sheet S ₁ and the second sheet S are placed on the staple plate 46 from which the discharge of the first sheet S has been completed.
_The paper is output in synchronization with ₂ .

Next, a process of aligning the sheets S stacked on the discharge tray 56 with the discharge rollers 53 and the discharge tray 56 will be described below. In the following description, the description will be made in the staple (multi) mode in which the consistency of the sheet S on the discharge tray 56 is particularly important.

[0047] First, the bookbinding sheet S bookbinding processing has been performed on the staple plate 46, as shown in FIG. 17 (a), the advancing movement in the D ₁ direction of the extrusion member 52, G of the discharge roller 53 Once discharged onto bearing surface 56c by the rotation in _one direction, with the completion of the ejection of the bookbinding sheet S onto the bearing surface 56c, the maximum bookbinding number of sheets H ₂ directions discharge tray 56 is set in advance It is regressed. Next, the extruded member 52 that has completed discharging the bookbinding sheet S as described above is
As shown in FIG. 17B, D ₂ is prepared for the next bookbinding process.
It is regressed in the direction. On the other hand, a discharge tray 56 supporting the bookbinding sheet S is advanced moved in H ₁ direction to a position sandwiched bookbinding sheet S between the discharge roller 53. Then, as described above, the discharge roller 53 and the discharge tray 56
Bookbinding sheet S sandwiched between, as shown in FIG. 17 (c), N by the rotation of the G ₁ direction of the discharge roller 53
Direction, and the rear end is
And alignment is performed on the discharge tray 56.

In the alignment of the bookbinding sheets S on the discharge tray 56 as described above, the binding portions St of the bookbinding sheets S which are higher than the other portions due to the stacking of a plurality of portions as shown in FIG. As shown in FIG. 19, the sheet falls into the notch 56b of the discharge tray 56 by its own weight. Also, as shown in FIG. 20 (a), even in the case of the bookbinding sheet S in which the drop into the notch portion 56b due to its own weight is limited, the book sheet post-processing apparatus 40 performs the bookbinding as shown in FIG. The sheet S is sandwiched between the discharge roller 53 and the discharge tray 56, and the binding portion St is pressed into the notch portion 56b, so that the bound sheet S on the discharge tray 56 caused by the binding portion St jumping up. It is designed to avoid a drop in consistency.

Further, in stacking the bookbinding sheets S on the discharge tray 56 as described above, the book post-processing device 4
In the zero discharge tray 56, the spring 61 contracts in accordance with the amount of bookbinding sheets S stacked on the support surface 56c, and the tray angle α between the support surface 56c and the escape portion 56a is changed. I have. For this reason, when the amount of the bookbinding sheets S stacked on the discharge tray 56 is small as shown in FIG. 21A, the spring 61 hardly contracts, and the support surface 56c of the discharge tray 56 is The bookbinding sheet S that is disposed on substantially the same plane as the upper surface of the plate 46 and that is discharged from the stapling plate 46 is supported in an optimal state. On the other hand, as shown in FIG. 21B, when the amount of bookbinding sheets S stacked on the discharge tray 56 is large, the spring 6
1 is contracted, and the tray angle α between the bearing surface 56c and the clearance 56a is approximately 180 degrees, so that the binding sheet S of the bookbinding sheet S caused by the step between the bearing surface 56c and the clearance 56a as shown in FIG. It is designed to prevent swelling.

The above embodiment does not limit the present invention, and various modifications can be made within the scope of the present invention.
In the above embodiment, the discharge tray 5 supporting the binding sheets S
By moving the sheet 6 upward, the bookbinding sheet S is sandwiched between the discharge roller 53 and the discharge tray 56 to align the bookbinding sheet S. In particular, the present invention is limited to such a configuration. Not something. For example, as shown in FIG.
A sponge roller 63 is provided rotatably in the O ₁ -O ₂ direction about the rotation axis of the discharge roller 53, and an interlocking belt 64 is wound between the sponge roller 63 and the discharge roller 53. while rotating the O ₁ direction by its own weight, the discharge with a sponge roller 63 rotating in the direction P in accordance with the rotation of the G ₁ direction of the discharge roller 53 tray 56
It is also possible to sandwich and align the above bookbinding sheet S. In such a case, since the sponge roller 63 for sandwiching the bookbinding sheet S with the discharge tray 56 is provided rotatably in the O ₁ -O ₂ direction, the stop position of the discharge tray 56 slightly varies. Is generated, this variation is absorbed on the sponge roller 63 side, so that there is almost no change in the pressing force on the bookbinding sheet S.

The tray angle adjusting means for changing the tray angle α between the bearing surface 56c of the discharge tray 56 and the relief portion 56a is not particularly limited to the spring 61. For example, the amount of bookbinding sheets S stacked on the discharge tray 56 is counted by a counting unit (not shown), and a cam unit 65 shown in FIG. 24, a crank unit 66 shown in FIG. , The tray angle α can be automatically controlled.

[0052]

As described above, in the sheet post-processing apparatus according to the first aspect of the present invention, the discharge tray is attached to the apparatus at a position below the discharge means, and the binding portion of the bound sheet is bound. A notch for releasing the sheet is formed on the surface facing the discharge means, and at least one of the discharge tray and the discharge means is provided so as to be able to advance and retreat in the vertical direction, so that the sheet on the discharge tray is provided. Is sandwiched between discharge means.

Thus, even when the bound sheets are stacked on the discharge tray, the sheets are sandwiched between the discharge means and the discharge tray, and the binding portion of the sheet is inserted into the cutout of the discharge tray. By pressing down, it is possible to reliably prevent the binding portion of the sheet from jumping up on the discharge tray without expanding the cutout area of the discharge tray unlike the conventional example, and as a result, binding on the discharge tray. There is an effect that it is possible to improve the consistency of the sheet thus set.

According to a second aspect of the present invention, in the sheet post-processing apparatus, the discharge tray is inclined from a position where the discharge tray is attached to the image forming apparatus.
The upper part of the discharge tray
A concave recess for the discharge means is formed on the upper surface of the discharge tray , and a position above the relief on the upper surface of the discharge tray.
In addition, a bearing surface for receiving the sheet is formed following the clearance.
Since the bearing surface is provided so as to be able to move up and down in the vertical direction, the bearing surface can be arranged on the same plane as the upper surface of the post-processing plate, and the bearing surface can be moved forward and backward to the discharge tray.
By providing the tray angle adjusting means for moving, the tray angle between the bearing surface and the relief portion can be set on the discharge tray.
Is variable in accordance with the amount of sheets to be stacked .

Thus, the tray angle of the discharge tray can be appropriately set according to the amount of sheets stacked on the discharge tray. For this reason, when the amount of stacked sheets is small, the bearing surface is arranged at a position where the sheets are optimally supported, while when the amount of stacked sheets is large, the bearing surface and the relief portion Are arranged substantially in a straight line, an effect is obtained that swelling of the sheet due to a step between the bearing surface and the relief portion can be avoided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a copying machine according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a sheet post-processing apparatus constituting the copying machine.

FIG. 3 is an explanatory diagram showing each sheet detection switch provided in a post-processing conveyance path constituting the above-described sheet post-processing apparatus.

FIG. 4 is an explanatory diagram showing a sheet detection switch constituted by a discharge roller and a driven roller constituting the above-mentioned sheet post-processing apparatus.

FIG. 5 is a perspective view showing an actuator disposed on the discharge roller.

FIGS. 6A and 6B are explanatory views showing an operation of detecting an upper limit of a discharge tray by an actuator.

FIG. 7 is a perspective view showing a cutout portion formed in the discharge tray.

FIG. 8 is a longitudinal sectional view showing a spring provided on the discharge tray.

FIG. 9 is a flowchart showing an operation process in the offset mode of the sheet post-processing apparatus.

FIG. 10 is a flowchart showing an operation process in a staple (single) mode of the sheet post-processing apparatus.

FIG. 11 is a flowchart illustrating a part of an operation process in a staple (multi) mode of the sheet post-processing apparatus.

FIG. 12 is a flowchart showing a part of an operation process in the staple (multi) mode of the sheet post-processing apparatus.

FIG. 13 is a flowchart showing a part of an operation process in the staple (multi) mode of the sheet post-processing apparatus.

FIG. 14 is a flowchart showing a part of an operation process in a staple (multi) mode of the sheet post-processing apparatus.

FIG. 15 is a flowchart showing a part of an operation process in the staple (multi) mode of the sheet post-processing apparatus.

FIGS. 16 (a), (b) and (c) are explanatory views showing a sheet conveying operation in a post-processing conveying path in a staple (multi) mode.

FIGS. 17 (a), (b) and (c) are explanatory views showing the operation of aligning a bookbinding sheet on a discharge tray in a staple (multi) mode.

FIG. 18 is a perspective view showing a plurality of stacked bookbinding sheets.

FIG. 19 is a perspective view showing a state in which the bookbinding sheets are stacked on a discharge tray.

FIGS. 20A and 20B are explanatory views showing a state in which a bookbinding sheet is sandwiched and aligned between a discharge roller and a discharge tray.

FIGS. 21A and 21B are explanatory diagrams showing states in which the tray angle between the bearing surface and the relief portion is changed according to the amount of bookbinding sheets stacked on the discharge tray. It is.

FIG. 22 is an explanatory diagram showing a state in which a bookbinding sheet on a discharge tray swells due to a step between a bearing surface and a relief portion.

FIG. 23 is a longitudinal sectional view showing a sponge roller rotatably provided on a rotation shaft of a discharge roller.

FIG. 24 is an explanatory view showing a tray angle adjusting means constituted by a cam unit.

FIG. 25 is an explanatory view showing a tray angle adjusting means constituted by a crank unit.

FIG. 26A is an explanatory view showing an operation in a staple mode by a conventional sheet post-processing apparatus, and FIG. 26B is a view showing an operation in an offset mode by the sheet post-processing apparatus. It is explanatory drawing which shows operation | movement.

FIG. 27 is a perspective view showing a discharge tray constituting the sheet post-processing apparatus.

FIG. 28 is a perspective view showing a state where bookbinding sheets are stacked on the discharge tray.

[Explanation of symbols]

 Reference Signs List 1 body body (image forming apparatus) 40 sheet post-processing device 45 bookbinding means 46 staple plate (post-processing plate) 53 discharge roller (discharge means) 56 discharge tray 56a relief portion 56b notch portion 56c support surface 61 spring (tray angle adjustment) Means) S Sheet St Binding part α Tray angle

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-327462 (JP, A) JP-A-2-23150 (JP, A) JP-A-63-66060 (JP, A) JP-A-63-63 267666 (JP, A) JP-A-63-41350 (JP, A) JP-A-61-217466 (JP, A) JP-A-62-60757 (JP, A) Japanese Utility Model Laid-Open No. 60-127947 (JP, U) 1-109058 (JP, U)

Claims (2)

(57) [Claims] An image forming apparatus for binding a sheet to be stacked on a post-processing plate by bookbinding means to perform bookbinding;
Then, in a sheet post-processing apparatus for discharging the bound sheets to a discharge tray by a discharge means provided at one end of the post-processing plate on the discharge side, the discharge tray is attached to the apparatus at a position below the discharge means. A notch for releasing the binding portion of the bound sheet is formed on the surface facing the discharge means, and at least one of the discharge tray and the discharge means moves up and down in the vertical direction. A sheet post-processing apparatus, which is provided so as to sandwich a sheet on a discharge tray between the sheet and a discharge unit. 2. After performing predetermined post-processing on a sheet carried in from an image forming apparatus and stacked on a post-processing plate, the post-processed sheet is placed on one end of the post-processing plate on the discharge side. By the provided discharging means, an image is formed at a position below the discharging means.
In the sheet post-processing apparatus for discharging to a discharge tray attached to an image forming apparatus, the discharge tray is inclined from a position where the sheet is attached to the image forming apparatus.
The upper part of the discharge tray
A concave recess for the discharge means is formed on the upper surface of the discharge tray , and a position above the relief on the upper surface of the discharge tray.
In addition, a bearing surface for receiving the sheet is formed following the clearance.
Since the bearing surface is provided so as to be able to move up and down in the vertical direction, the bearing surface can be arranged on the same plane as the upper surface of the post-processing plate, and the bearing surface can be moved forward and backward to the discharge tray.
By providing the tray angle adjusting means for moving, the tray angle between the bearing surface and the relief portion can be set on the discharge tray.
A sheet post-processing device that varies according to the amount of sheets stacked on the sheet.